Hoverflies, Hoverflies, and a few Moths – July 26
We are now past the longest day of the year and the days are getting shorter and the nights longer. Yet, as I sit down to write this article, we seem to be in the grip of another heatwave—the second, or perhaps the third of the summer. I've honestly lost count.
Many of you have been out spotting hoverflies and sharing your sightings, which is wonderful to see. I hope my article, notes and ‘Hoverflies on the Wing’ collations are helping you discover more of these fabulous flies. I know I’ve certainly been seeing a wider variety of species this year, although I can’t help wondering how the recent spells of hot weather have been affecting them.
Hoverflies are often known as “sun flies” because they become active when the sun shines. However, they are surprisingly sensitive to temperature and, like Goldilocks, prefer conditions that are ‘just right’. When temperatures fall below around 8°C, many species enter a state of torpor and become inactive. At the other extreme, when temperatures climb above 25°C, hoverflies often retreat into shade or sheltered spots to avoid overheating.
In many ways, I’ve behaved much like the hoverflies during this latest heatwave, seeking refuge from the hottest part of the day whenever possible. Despite the high temperatures, I’ve still managed to get out with the Yorkshire Naturalists’ Union, lead a session for the Barnsley Naturalist Association, and even fit in a little moth trapping in my garden.